Q35 — AWS SOA-C02 Ch.1

Question 35 of 100 | ← Chapter 1

A company recently deployed an application in production. The production environment currently runs on a single Amazon EC2 instance that hosts the application's web application and a MariaDB database. Company policy states that all IT production environments must be highly available. What should a SysOps administrator do to meet this requirement?

• A. Migrate the database from the EC2 instance to an Amazon RDS for MariaDB Multi-AZ DB instance. Run the application on EC2 instances that are in an Auto Scaling group that extends across multiple Availability Zones. Place the EC2 instances behind a load balancer. ✓
• B. Migrate the database from the EC2 instance to an Amazon RDS for MariaDB Multi-AZ DB instance. Use AWS Application Migration Service to convert the application into an AWS Lambda function. Specify the Multi-AZ option for the Lambda function.
• C. Copy the database to a different EC2 instance in a different Availability Zone. Use AWS Backup to create Amazon Machine Images (AMIs) of the application EC2 instance and the database EC2 instance. Create an AWS Lambda function that performs health checks every minute. In case of failure, configure the Lambda function to launch a new EC2 instance from the AMIs that AWS Backup created.
• D. Migrate the database to a different EC2 instance. Place the application EC2 instance in an Auto Scaling group that extends across multiple Availability Zones. Create an Amazon Machine Image (AMI) from the database EC2 instance. Use the AMI to launch a second database EC2 instance in a different Availability Zone. Put the second database EC2 instance in the stopped state. Use the second database EC2 instance as a standby.

Correct Answer: A. Migrate the database from the EC2 instance to an Amazon RDS for MariaDB Multi-AZ DB instance. Run the application on EC2 instances that are in an Auto Scaling group that extends across multiple Availability Zones. Place the EC2 instances behind a load balancer.

Explanation

AWS高可用性设计通常要求资源跨多个可用区（AZ）分布，并利用托管服务减少运维负担。题目中当前架构的单点故障在于Web应用和数据库共存于单个EC2实例。AWS文档指出，RDS Multi-AZ通过主备副本自动处理数据库故障转移，确保数据库层高可用。应用层的高可用需结合Auto Scaling组跨AZ部署实例，并配合负载均衡器分发请求，实现水平扩展和弹性。选项A同时解决数据库（RDS Multi-AZ）和应用层（Auto Scaling+负载均衡器）的高可用需求，符合最佳实践。其他选项未完全满足自动化跨AZ冗余或误用服务功能（如Lambda的Multi-AZ选项不存在）。